I did not use Priceline for hotels in Italy, but I
have used them for elsewhere in Europe.

I just used Priceline for Brussels and a hotel near
CDG Airport near Paris. You can go to
http://www.biddingfortravel.com to see which hotels have
accepted bids on Priceline, and what prices successful
bidders got. That gave me the info and strategy I
needed to get my bid accepted.

Generally I want to pick my hotel, but getting the
Marriott Brussels for $65/night and the Courtyard by
Marriott at CDG Airport for $41 lets me splurge in
Venice and the Italian Riviera!